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Pulleniatina obliquiloculata shells from 16 core-top samples from the tropical Indo-Pacific Oceans are analyzed for the ratios of boron and cadmium to calcium(B/Ca and Cd/Ca). The B/Ca ratios show a very weak positive relationship with [B(OH)_4~-] and the dissolved carbonate species at the apparent calcification depth of P.obliquiloculata. The boron partition coefficients(K_D) between P. obliquiloculata B/Ca and seawater[B(OH)_4~-]/[HCO_3~-] distribute around 1.1×10~(-3)-1.3×10~(-3) with a mean value of(1.19±0.12)×10~(-3),and are significantly related to the nutrient concentration, especially phosphate. The lack of any clear correlation between the P. obliquiloculata B/Ca and seawater carbonate chemical parameters suggests that the physiochemical controls on boron incorporation are masked by the complexity of natural seawater condition. But the significant dependence of Ku on nutrient may likely be explained by a nutrient related growth-rate effect. Cd/Ca of P.obliquiloculata shows significant correlation with seawater phosphate concentration, and its partition coefficients(D_(cd)) are significantly related to temperature. A first-principle methodology of P. obliquiloculata B/Ca is applied;with the aid of Cd/Ca as a phosphate proxy and a constraint on K_D, to estimating sea water carbonate chemistry(e.g., pH). The results are fairly promising and allow us to propose the possibility to apply the combination of B/Ca and Cd/Ca proxies(and also Mg/Ca and δ~(18)O for estimating temperature and salinity) for the paleoreconstruction of seawater carbonate chemistry. 相似文献
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在传统上,浮游有孔虫Ｇｌｏｂｏｒｏｔａｌｉａｔｒｕｎｃａｔｕｌｉｎｏｉｄｅｓ的初现面一直被用来作为划定海相地层更新统下界的可靠依据。然而,此一初现面（２．０ＭａＢ．Ｐ．）所界定的更新统下界与超微化石Ｇａｐｈｙｒｏｃｏｐｓａｏｃｅａｎｉｃａｓ．ｌ．初现面（１．６７～１．７ＭａＢ．Ｐ．）所界定的并不一致。这一现象对大陆边缘的沉积地层尤为显著。其主要原因是,大陆边缘的高沉积速率会导致两个基面有很的层位间距。本研究证明台湾西南部二仁溪剖面之浮游有孔虫Ｐｕｌｌｅｎｉａｔｉｎａ最后一次的旋向变化（由左至右）,几乎与超微化石Ｇ．ｏｃｅａｎｉｃａｓ．ｌ．的初现面同一时间。因此,就浮游有孔虫生物地层的观点看,此一族向变化是辨识更新统下界的一个非常有用的基面。 相似文献
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南海南部普林虫与“中更新世革命” 总被引：6，自引：2，他引：4
对南海南部ODP 1143站2.1 Ma以来沉积物中的浮游有孔虫群进行研究, 发现在冲绳海槽及南海北部普遍被认为是黑潮标志种的Pulleniatina obliquiloculata在中更新世革命(MPR)前后对冰期旋回的响应截然相反; 且在MPR之后的变化与南海北部和冲绳海槽相反, 即冰期时含量高而间冰期时低.交叉频谱分析和相位分析的结果也证实了ODP 1143站P.obliquiloculata与全球冰量变化之间的上述关系.该种在MPR前后冰期旋回的转变, 可能是由于MPR之后南海南部在冰期时切断了与印度洋之间的海水交换, 或者是冰期时海水盐度增加等因素引起的上部水体结构的重大改观所致. 相似文献
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在传统上,浮游有孔虫Ｇｌｏｂｏｒｏｔａｌｉａｔｒｕｎｃａｔｕｌｉｎｏｉｄｅｓ的初现面一直被用来作为划定海相地层更新统下界的可靠依据。然而,此一初现面(２．０ＭａＢ．Ｐ．)所界定的更新统下界与超微化石Ｇａｐｈｙｒｏｃｏｐｓａｏｃｅａｎｉｃａｓ．ｌ．初现面(１．６７～１．７ＭａＢ．Ｐ．)所界定的并不一致。这一现象对大陆边缘的沉积地层尤为显著。其主要原因是,大陆边缘的高沉积速率会导致两个基面有很的层位间距。本研究证明台湾西南部二仁溪剖面之浮游有孔虫Ｐｕｌｌｅｎｉａｔｉｎａ最后一次的旋向变化(由左至右),几乎与超微化石Ｇ．ｏｃｅａｎｉｃａｓ．ｌ．的初现面同一时间。因此,就浮游有孔虫生物地层的观点看,此一族向变化是辨识更新统下界的一个非常有用的基面。 相似文献
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